This application claims priority to German Patent Application No. 102 14 391.9, filed Mar. 30, 2002, the disclosure of which is incorporated herein by reference.
The invention relates to a device on, for example, a carding machine for cotton, synthetic fibers and the like. The device comprises at least one flat bar with flat bar clothing, where the flat bar clothing is attached to the flat bar and is positioned opposite clothing on, for example, a main carding cylinder of the carding machine. The clothing is attached to a support provided with fastening elements that engage the flat bar.
The flat bar of a known device has of a back part and a support body with an underside. A clothing strip (flexible clothing) is attached to the underside (the part that holds the clothing) and extends along the underside. The clothing strip comprises a support element having several textile layers in which a plurality of small wire hooks or clothing needle points are fastened. The clothing strip is attached with the aid of two clamps, straps, or clips along the longitudinal sides of the support body. With one end, the clamps encircle the longitudinal edge regions of the clothing strip and, with the other end, they engage recesses in the support body. In practical operations, the clamps consist of a sheet-metal strip, one longitudinal edge of which is punched into the textile material. During assembly, the textile material of the clothing strip is attached with considerable tension and is form fitting to the support body of the flat bar. In the process, the clamps exert tensile forces in such a way that the textile material is deformed spherically away from the underside. Thus, the clothing needle points are also arranged in an undesirable manner along a convex enveloping curve, pointing toward the outside.
A set of flat bars produced in this way has an accuracy of 0.05 mm in height and evenness when not in use. As a result of use, the height differences in the set will increase to approximately 0.2 mm. The accuracy is improved only insignificantly through a re-sharpening of the clothing on the machine. Following a fiber-material throughput of approximately 400 t, the flat bar clothing is worn to such a degree that it must be replaced. The flat bar is clamped down for dismantling the sheet metal straps and the form-fitting connection is reversed with the aid of a lever and pliers. The considerable forces required for the assembly and dismantling negatively effect the dimensional stability of the flat bar. Added to this are undesirable tolerances resulting from the production of the flat bar body. As a result of the aforementioned disadvantages, the clothing needle points of the clothed flat bar must be leveled by grinding.
According to a previous solution (shown in European Patent 0 887 445), the bottom surface is provided with two side walls that project in a downward direction. The base is not glued directly to the bottom surface, but to a flexible band, wherein this band has side parts that cooperate with the projections on the bottom surface in the manner of clip-on connections, thus fastening the clothing strips to the profile. The side walls are thus extended downward to protect the longitudinal edges of the base. The production of this type of flat bar is expensive with respect to production technology and assembly. In particular, it is problematic that the flexible band does not provide sufficient hold for the clothing strip during operation. The flexibility, which counteracts the important spacing stability between the clothing points of the flat bar clothing and the clothing points on the cylinder clothing, is a disadvantage that results in an uneven carding effect and can also cause operational malfunctions.
In contrast to the above, it is an object of the invention to create a device of the above-described type that avoids the aforementioned disadvantages. In particular, the invention makes it possible to produce a clothed flat bar with stable form and makes it easier to produce the flat bar and replace the clothing strip.
This and other objects are achieved by a device for use in a carding machine having a roller with clothing, the device being for arranging opposite the clothing on the roller. The device has a flat bar, a clothing strip, and a rigid support element connected to the clothing strip and having fastening elements. The fastening elements engage the flat bar and exert pressure on the flat bar.
Owing to the fact that the support connected to the clothing strip has a rigid design and the fastening elements are elastically connected to the support, an operationally safe embodiment is achieved which also permits easy replacement of worn clothing. If the clothing is worn, the complete unit, including the clothing strip with clothing and support with fastening elements, is removed with few manipulations from the support body and is discarded. Another advantage is that all production tolerances of the flat bar, the clothing as well as those resulting from the assembly (including the dismantling) are eliminated. With the flat bar clothed according to the invention, the addition of tolerances developing during the assembly and dismantling of the flat bar clothing, the technologically damaging leveling and the worsening of the accuracy during use are advantageously and effectively avoided.